first question is i'm trying to write a program the "pure api" way and i've got everything working but its taking all the CPUs time.

2nd, im assisting in a computer science 4 class and the teacher is new (he's just learning C++ with the students) and he wants to know about namespaces. So i told him what they're for and that you need something to the affect of using namespace std; for all the new header files and that its recommended that you use the new header files, but he still wants to know why? im not sure if i understand what he's asking, maybe he wants to know why microsoft made new headers for things and put everything in a standard namespace?